Frame for a heat engine

ABSTRACT

A thermal management system for a heat engine, the system including an forming at least in part a core flowpath and a cavity, wherein the core flowpath and the cavity are separated by a double wall structure formed by at least a portion of inner wall, and wherein the double wall structure includes a plenum. A first opening provides fluid communication between the cavity and the plenum, and a second opening provides fluid communication between the plenum and the core flowpath. The inner wall is configured to receive a first flow of fluid. An outer wall forms a passage extended at least partially around the core flowpath. The outer wall is configured to receive a second flow of fluid fluidly separated from the core flowpath.

FIELD

The present subject matter relates generally to casings or frames forheat engines. The present subject matter relates more particularly tocasings or frames including fluid passages. The present subject mattermore particularly relates to casings and frames for turbo machines.

BACKGROUND

Precipitation or debris that enters an engine may cause significantdamage to internal components, such as if ingested into a flowpath.Anti-icing systems generally attempt to remove or mitigate creation oraccumulation of ice, snow, or other debris that may build up at theinlet of an engine.

Known anti-icing systems may insulate a portion of an inlet duct, orprovide heat to a portion of an inlet duct. However, known systems mayinsufficiently heat the inlet duct. Other known systems may provide heatbut also distort the geometry of the inlet duct, such that inlet airflowmay be distorted as it arrives at a compressor, which may lead toasymmetric airflows and diminished operability or performance of thecompressor.

Furthermore, it is generally a requirement to reduce weight whileproviding for features that may accommodate fluid passages, anti-icing,structural integrity for, mounting, and aerodynamic performance. Assuch, there is a need for an improved inlet duct. Additionally, there isa need for thermal management systems that can alleviate one or more ofissues related to icing, foreign object debris, and mitigating inletdistortion.

BRIEF DESCRIPTION

Aspects and advantages of the invention will be set forth in part in thefollowing description, or may be obvious from the description, or may belearned through practice of the invention.

An aspect of the present disclosure is directed to a thermal managementsystem for a heat engine, the system including an inner wall and anouter wall. The inner wall is extended from an inlet end to an outletend, the inner wall forming at least in part a core flowpath and acavity. The core flowpath and the cavity are separated by a double wallstructure formed by at least a portion of inner wall. The double wallstructure includes a plenum, a first opening providing fluidcommunication between the cavity and the plenum, and a second openingproviding fluid communication between the plenum and the core flowpath,the inner wall configured to receive a first flow of fluid. The outerwall is extended from the inlet end toward the outlet end. The outerwall forms a passage extended at least partially around the coreflowpath. The outer wall at least partially forms the core flowpath. Theouter wall is configured to receive a second flow of fluid fluidlyseparated from the core flowpath.

Another aspect of the present disclosure is directed to a turbo machinedefining an inlet end and an outlet end and a core flowpath. The turbomachine includes a compressor section configured to generate a firstflow of fluid, a fluid system configured to generate a second flow offluid to the passage, and an inlet frame wherein the compressor sectionis positioned at the outlet end of inlet frame. The inlet frame includesan inner wall extended from the inlet end to the outlet end and formingat least in part the core flowpath and a cavity. The cavity ispositioned inward of the inner wall. The core flowpath and the cavityare separated by a double wall structure formed by at least a portion ofthe inner wall. The double wall structure includes a plenum extendedfrom the inlet end toward the outlet end of the inlet frame. A firstopening provides fluid communication between the cavity and the plenum,and a second opening provides fluid communication between the plenum andthe core flowpath. The inner wall is configured to receive the firstflow of fluid from the compressor section. An outer wall is extendedfrom the inlet end toward the outlet end of the frame and forms apassage extended at least partially around the core flowpath. The outerwall at least partially forms the core flowpath and is configured toreceive the second flow of fluid from the fluid system. The second flowis fluidly separated from the first flow of fluid.

These and other features, aspects and advantages of the presentinvention will become better understood with reference to the followingdescription and appended claims. The accompanying drawings, which areincorporated in and constitute a part of this specification, illustrateembodiments of the invention and, together with the description, serveto explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including thebest mode thereof, directed to one of ordinary skill in the art, is setforth in the specification, which makes reference to the appendedfigures, in which:

FIG. 1 is a schematic cross sectional view of an exemplary thermalmanagement system at a heat engine according to an aspect of the presentdisclosure;

FIG. 2 is a perspective view of a portion of an exemplary embodiment ofa gas turbine engine including a thermal management system according toan aspect of the present disclosure;

FIG. 3 is a cross sectional view of a portion of an embodiment of aframe for a heat engine according to an aspect of the presentdisclosure;

FIG. 4 is a detailed cross sectional view of a portion of an embodimentof a frame for a heat engine according to an aspect of the presentdisclosure;

FIG. 5 is a perspective view of a portion of an embodiment of a framefor a heat engine according to an aspect of the present disclosure;

FIG. 6 is a sectional view at plane 6-6 of the embodiment of the framedepicted in regard to FIG. 5;

FIG. 7 is a perspective view of an embodiment of a frame for a heatengine according to an aspect of the present disclosure;

FIG. 8 is a partially transparent view of an embodiment of a frame for aheat engine according to an aspect of the present disclosure;

FIG. 9 is a side view of an embodiment of a frame for a heat engineaccording to an aspect of the present disclosure;

FIG. 10 is a schematic diagram of an embodiment of a thermal managementsystem according to an aspect of the present disclosure;

FIG. 11 is a schematic diagram of another embodiment of a thermalmanagement system according to an aspect of the present disclosure;

FIG. 12 is a partially transparent view of an embodiment of a frame fora heat engine according to an aspect of the present disclosure;

FIG. 13 is a partially transparent view of another embodiment of a framefor a heat engine according to an aspect of the present disclosure;

FIG. 14 is a partially transparent view of a portion of an embodiment ofa frame according to an aspect of the present disclosure;

FIG. 15 is a cutaway perspective view at plane 15-15 of an embodiment ofthe frame of FIG. 3; and

FIG. 16 is a flowpath view of a portion of the cutaway view of theembodiment at plane 15-15 of FIG. 15.

Repeat use of reference characters in the present specification anddrawings is intended to represent the same or analogous features orelements of the present invention.

DETAILED DESCRIPTION

Reference now will be made in detail to embodiments of the invention,one or more examples of which are illustrated in the drawings. Eachexample is provided by way of explanation of the invention, notlimitation of the invention. In fact, it will be apparent to thoseskilled in the art that various modifications and variations can be madein the present invention without departing from the scope or spirit ofthe invention. For instance, features illustrated or described as partof one embodiment can be used with another embodiment to yield a stillfurther embodiment. Thus, it is intended that the present inventioncovers such modifications and variations as come within the scope of theappended claims and their equivalents.

As used herein, the terms “first”, “second”, and “third” may be usedinterchangeably to distinguish one component from another and are notintended to signify location or importance of the individual components.

The terms “upstream” and “downstream” refer to the relative directionwith respect to fluid flow in a fluid pathway. For example, “upstream”refers to the direction from which the fluid flows, and “downstream”refers to the direction to which the fluid flows.

Referring now to the drawings, FIG. 1 provides a schematiccross-sectional view of an exemplary thermal management system inaccordance with an aspect of the present disclosure. In variousembodiments, the thermal management system may be configured as anengine 10. The engine 10 may be configured as a gas turbine engine orturbo machine generally, or a turboprop, turboshaft, turbofan, turbojet,propfan or unducted fan, or other specific turbo machine configuration.In other embodiments, the engine 10 may be configured as a heat engineor Brayton Cycle machine generally, in which a flow of oxidizer isprovided an utilized to produce thrust, power, torque, or anotherdesired output. Still further, although the embodiment depicted inregard to FIG. 1 depicts a substantially straight flow through theengine, it should be appreciated that the engine 10 may be configured asa reverse-flow engine in which a flow of oxidizer and/or gasestherethrough flow or egress in a direction opposite of an inlet or exitof the engine.

As shown in FIG. 1, the engine 10 defines a longitudinal or axialcenterline axis 12 extending through for reference. A radial direction Ris extended from the centerline axis 12. The engine 10 may generallyinclude a substantially tubular outer casing 14 formed from a singlecasing or multiple casings, such as one or more castings, forgings,machined structures, or additively manufactured structures. One or moreof the casings 14 may include a frame 100 such as further describedherein. In certain embodiments, the frame 100 is positioned at anoxidizer inlet end 102 of the engine 10. It should therefore beappreciated that the inlet end 102 refers to a direction from whichoxidizer (e.g., air) flows into a structure (i.e., an upstream end),such as the engine 10 generally, or the frame 100 specifically. Invarious embodiments depicted herein, the frame 100 defines an inletframe or casing receiving gases and providing at least a portion of thereceived air to one or more of a compressor section 21, a combustionsection 26, a turbine section 31, or an exhaust section 35 of the engine10. In certain embodiments, the frame 100 depicted herein defines aninlet frame or casing positioned forward or upstream of the compressorsection 21 and configured to receive a flow of ambient air and provideall or part of the flow of air to the compressor section 21, such asfurther described herein.

The outer casing 14 encloses, in serial flow relationship, thecompressor section 21, the combustion section 26, the turbine section31, and the exhaust section 35. A core flowpath 78 is defined throughthe engine 10, in which the core flowpath 78 defines a primary pathwaythrough which compressed air is generated, mixed, andcombusted/detonated to produce work or torque at the turbine section 31.The compressor section 21 includes an annular array of inlet guide vanes22, one or more sequential stages of compressor rotors 23 (e.g.,including an axial and/or centrifugal compressor) and one or moresequential stages of one or more stages of stationary or variable vanes24.

The combustion section 26 includes a combustion chamber 27 and one ormore fuel nozzles 28 extending into the combustion chamber 27. The fuelnozzles 28 supply liquid and/or gaseous fuel to mix with compressed airentering the combustion chamber 27. Further, the mixture of fuel andcompressed air combust or detonate within the combustion chamber 27 toform combustion gases 29. As will be described below in more detail, thecombustion gases 29 drive both the compressor section 21 and the turbinesection 31.

The turbine section 31 includes one or more turbine rotors 33 drivinglyconnected to one or more compressor rotors 23. The turbine section 31includes one or more sequential stages of turbine rotors 33 and one ormore sequential stages of stator vanes 32. In certain embodiments, theturbine section 31 includes a power turbine 34 including one or moresequential stages of turbine rotor blades and one or more sequentialstages of stator vanes. However, it should be appreciated that in otherembodiments, the turbine section 31 may include sequential stages ofcounter-rotating rotors without stages of stator vanes. As will bediscussed below in more detail, one or more of the turbine rotors 33drives one or more compressor rotors 23 via a driveshaft 36. The powerturbine 34 drives a power shaft 37. The power shaft 37 is operablyconnected to a power output device 38, such as, but not limited to, apropeller assembly, a fan assembly, a rotor assembly (e.g., for rotarywing aircraft), a turbine, an electric load device (e.g., motor and/orgenerator or other electric machine), a transmission or other gearassembly, or other desired power receiving device.

As shown in the embodiment illustrated in FIG. 1, the compressor section21 and the turbine section 31 are coupled to one another via thedriveshaft 36. During operation, the combustion gases 29 drive theturbine rotor 33 and the power turbine 34. As the turbine rotor 33rotates around the centerline axis 12, the compressor rotor 23 and thedriveshaft 36 both rotate around the centerline axis 12. Further, as thepower turbine 34 rotates, the power shaft 37 rotates and transfersrotational energy to the power output device 38.

Referring now to FIG. 2, a perspective view of a portion of an exemplaryembodiment of the engine 10 is provided. Referring also to FIG. 3, anaxial cross sectional view of a portion of an exemplary embodiment ofthe engine 10 is provided. The embodiments of the engine 10 provided inregard to FIGS. 2-3 may be configured substantially similarly to one ormore embodiments of the engine 10 shown and described in regard toFIG. 1. Referring to FIGS. 2-3, the engine 10 includes the frame 100positioned forward or upstream of the compressor section 21. In certainembodiments, the frame 100 is an inlet frame or casing. Althoughdepicted as a substantially annular casing or frame 100 extendedcircumferentially around the axial centerline axis 12, it should beappreciated that other embodiments of the frame 100 are two-dimensional,such as to include a height and width extended perimetrically (i.e.,extended along a continuous line forming a boundary of a polygonalfigure) from the axial centerline axis 12. In still other embodiments,the frame 100 may include a perimetric cross section (e.g., polygonalcross section, such as rectangular) transitioning to an annular crosssection along a direction of flow of fluid through the core flowpath 78.

As further shown and described herein, the frame 100 includesstructures, conduits, pathways, or manifolds configured to provide aflow of fluid through and at least partially around the frame 100. Assuch, in various embodiments, the frame 100 is an anti-icing systemconfigured to receive the flow of fluid for heat transfer to the frame.The structures shown and described herein in regard to the engine 10including embodiments of the frame 100 may be an integrated, monolithicstructure. Embodiments of the frame 100 provided herein may improveefficiency and/or performance of the engine 10, such as by reducing oreliminating a flow of oxidizer re-directed from the compressor section21 for anti-icing. For example, conventional engines, such as aircraftturbo machines, generally utilize oxidizer flow from a compressorsection for anti-icing at an engine structure, such as an inletstructure, nacelle, or other casing upstream of the compressor section.

Embodiments of the engine 10 including embodiments of the frame 100provided herein include structures, such as flowpaths, passages,conduits, etc. that provide a heated fluid to the frame 100 to reduce,mitigate, or eliminate icing at the inlet end 102 of the engine 10. Incertain embodiments described herein, the flow of fluid is a lubricant,hydraulic fluid, or fuel, or combinations thereof, directed to the frame100. The flow of fluid possesses thermal energy that is transferred tothe frame 100, such as to heat the frame and reduce or mitigate icing,thermal distortion, or other conditions that may adversely affectoperation of the engine 10. Such adverse conditions that may bemitigated or eliminated include inlet distortion, compressor stall orsurge, asymmetric airflows, or foreign object debris (FOD), such as FODthat may be attributable to icing at an inlet casing, or other losses toengine operability. Embodiments of the frame 100 provided herein mayfurther improve engine performance, such as by not requiring a flow ofoxidizer (e.g., compressed air) to the frame 100 from the compressorsection 21. As such, relatively more oxidizer is available to thecombustion section 26 for mixing with fuel and generation of combustiongases in contrast to conventional engines, thereby allowing for improvedperformance and/or efficiency relative to an amount of fuel, rotationalspeed, and performance parameter of the engine without embodiments ofthe frame 100 provided herein.

The frame 100 includes an inlet end 102 and an outlet end 104 betweenwhich a portion of the core flowpath 78 at the frame 100 is defined. Thecore flowpath 78 extends from the inlet end 102 outward along the radialdirection R and then inward along the radial direction R toward theoutlet end 104. Proximate to the outlet end 104 is a first strut 110extended radially across a primary flowpath 77 defined at the coreflowpath 78 at the frame 100. In certain embodiments, the first strut110 defines, at least in part, the outlet end 104 of the frame 100 atthe core flowpath 78. In still certain embodiments, a second strut 111is further extended radially through a secondary flowpath 79 radiallyoutward of the core flowpath 78. The second strut 111 defined, at leastin part, a second exit end 106 of the frame 100 at the secondaryflowpath 79.

In various embodiments, the frame 100 includes a splitter 112 separatingthe core flowpath 78 to a primary flowpath 77 and the secondary flowpath79. The struts 110, 111 are positioned at the splitter 112. The primaryflowpath 77 is a first portion of the frame 100 extended in fluidcommunication to a core engine (e.g., all or part of the compressorsection 21, the combustion section 26, and the turbine section 31)downstream of the frame 100, such as to the compressor section 21. Thesecondary flowpath 79 is a second portion of the frame 100 extendedgenerally around the core engine, such as, but not limited to, a bypassflowpath, a third stream flowpath, a bleed system, or other flowpath forthe engine 10 or an associated apparatus (e.g., an aircraft, vehicle, orsystem to which the engine 10 is attached). The first strut 110 isextended radially through the primary flowpath 77 at the outlet end 104.The second strut 111 is further extended radially through the secondaryflowpath 79.

In still various embodiments, one or more manifolds or conduits 114 isextended through the struts 110, 111 and the splitter 112. The conduits114 provide and/or egress one or more fluids to or from the frame 100.Referring to FIG. 3, in one embodiment, the conduit 114 provides fluidcommunication from radially outward portions of the frame 100 to one ormore bearing assemblies 150 radially inward of an inner wall 120 of theframe 100.

Referring still to FIGS. 2-3, the frame 100 includes an inner wall 120extended from the inlet end 102 to the outlet end 104. The frame 100further includes an outer wall 130 extended from the inlet end 102 to asecond outlet end 106 positioned at the secondary flowpath 79. Incertain embodiments, the outer wall 130 is extended from the inlet end102 to the second strut 111. In still certain embodiments, the innerwall 120 is extended from the inlet end 102 to the first strut 110 andthe first outlet end 104.

Referring now to FIG. 4, an exemplary embodiment of a portion of theengine 10 including the frame 100 is provided in further detail. Theembodiment depicted in regard to FIG. 4 is configured substantiallysimilarly as shown and described in regard to FIGS. 2-3. In variousembodiments, at least a portion of the inner wall 120 includes a doublewall structure 122 extended from the inlet end 102. The double wallstructure 122 includes an outer portion 123 in direct fluid contact withthe core flowpath 78. The double wall structure 122 further includes aninner portion 124 radially inward of the outer portion 123. A plenum 121is defined between the outer portion 123 and the inner portion 124. Invarious embodiments further depicted and described herein, the plenum121 is further sectioned into a plurality of plenums via one or morewalls extended between the outer portion 123 and the inner portion 124.

Referring to FIGS. 2-4, radially inward of the inner wall 120 and theinner portion 124 is a cavity 125. In certain embodiments, the cavity125 is an enclosed space or volume. The cavity 125 is defined at leastby the frame 100. In various embodiments, one or more other structuresmay further define the cavity 125, such as a shaft, shroud, torque tube,or sleeve 200.

The inner portion 124 of the double wall structure 122 of the inner wall120 includes one or more first plenum openings 126 providing fluidcommunication between the plenum 121 and the cavity 125. The inner wall120 further includes one or more second plenum openings 128 providingfluid communication between the plenum 121 and the core flowpath 78. Incertain embodiments, the second plenum opening 128 is defined throughthe outer portion 123 of the double wall structure 122 of the inner wall120. The first plenum opening 126 and the second plenum opening 128together allow for a fluid 91, such as an oxidizer, air, or inert gas,to flow from the cavity 125 into the plenum 121 and the core flowpath78. The flow of fluid therethrough may provide heat transfer to theframe 100, such as to provide anti-icing benefits such as describedherein.

In certain embodiments, a plurality of the first plenum openings 126 isdefined through the inner portion 124. In some embodiments, the frame100 includes at least one hundred first plenum openings 126 distributedcircumferentially or perimetrically through the inner portion 124 of thedouble wall structure 122. In other embodiments, the frame 100 includesat least five hundred first plenum openings 126 distributedcircumferentially or perimetrically through the inner portion 124 of thedouble wall structure 122. In particular embodiments, the frame 100includes at least nine hundred discrete first plenum openings 126distributed circumferentially or perimetrically through the innerportion 124 of the double wall structure 122. In still particularembodiments, the plurality of first plenum openings 126 is distributedaxially along the inner wall 120. As such, the flow of fluid 91 isallowed to enter into the plenum 91 throughout the axial distance of theplenum 91 and the double wall structure 122. For instance, the flow offluid 91 is permitted to enter the plenum 91 at or proximate to theinlet end 102 of the frame 100. The flow of fluid 91 is furtherpermitted to enter the plenum 91 distal to the inlet end 102, or moreproximate to the outlet end 104 of the frame 100. The flow of fluid 91is further permitted to enter the plenum 91 at a plurality of locationsbetween the inlet end 102 of the frame 100 and the outlet end 104 of theframe 100.

Referring to FIG. 4, in various embodiments, the second plenum opening128 is positioned at a downstream end of the double wall structure 122(i.e., the downstream end being downstream relative to the flow ofoxidizer 89 into the frame 100 to the core engine 18). Stateddifferently, in certain embodiments, the second plenum opening 128 ispositioned through the outer portion 123 of the double wall structure122 distal to the inlet end 102. The second plenum opening 128 isextended through the outer portion 123 of the inner wall 120 to permitthe flow of fluid 91 through the first plenum opening 126 and throughthe plenum 121 and egress into the core flowpath 78 through the secondplenum opening 128.

In various embodiments, the frame 100 includes a plurality of discretesecond plenum openings 128 distributed circumferentially orperimetrically through the inner wall 120. In some embodiments, aquantity of the second plenum openings 128 is equal to or less than aquantity of the first plenum openings 126. In other embodiments, a totalcross sectional area or volume of the second plenum openings 128 isequal to or less than a total cross sectional area or volume of thefirst plenum openings 126. In certain embodiments, positioning thesecond plenum opening 128 at the downstream end of the outer portion 123of the double wall structure 122 allows for the flow of fluid 91 toenter the plenum 91 and transfer heat along the axial distance of thedouble wall structure 122 before egressing into the core flowpath 78 viathe second plenum opening 128. In various embodiments, the second plenumopening 128 and the first plenum opening 126 are together configured toprovide desirable pressure difference and/or flow through the plenum121.

Positioning and/or ratios of the quantities of the second plenum opening128 and the first plenum opening 126 may provide particular benefitsrelated to heat transfer at the frame 100 that may further improveperformance of the engine 10. Such benefits include anti-icing at theinner wall 120, such as to prevent accumulation and/or ingestion of iceinto the core engine 18. Additionally, placement of the second plenumopening 128 distal to the inlet end 102 may permit desired accumulationof thermal energy in the plenum 121 and heat transfer to the double wallstructure 122, such as the outer portion 123 in particular. Theplurality of first plenum openings 126 may further provide particularbenefits not previously known or provided in anti-icing structures. Forinstance, the plurality of first plenum openings 126 may provideimproved heat transfer at the upstream end proximate to the inlet end102, where ice may be more prone to form or accumulate. The plurality offirst plenum openings 126 may further provide for collection of thermalenergy at the inlet end 102 at a forward collector 221 to mitigateformation or build-up of ice at the inlet end 102, such as furtherdescribed herein. The plurality of second plenum openings 128 mayfurther provide be positioned at an aft collector 222 distal to theinlet end 102 such as to provide a substantially uniform pressure and/orflow of fluid 92 egressed from the second plenum opening 128 into thecore flowpath 78, such as further described herein. The substantiallyuniform pressure and/or flow of fluid 92 into the core flowpath 78 maymitigate or eliminate adverse effects to inlet oxidizer conditions atthe compressor section 21 (FIGS. 1-2). For instance, positioning of thesecond plenum opening 128, the first plenum opening 126, and one or moreof the collectors 221, 222 may provide desired heat transfer at thedouble wall structure 122 to mitigate icing while further mitigatinginlet distortion at the frame 100 and/or mitigating formation ofdistorted airflow conditions into the compressor section 21 (FIGS. 1-2)that would be due to circumferential variations in temperature orpressure of oxidizer egressing the frame 100 and entering the compressorsection 21.

In some embodiments, the outer portion 123 of the double wall structure122 includes an inner surface 223 in the plenum 121. The inner surface223 includes a turbulator structure 323 (FIG. 6), such as to provide aturbulent boundary layer at the inner surface 223 of the double wallstructure 122 within the plenum 121. In various embodiments, theturbulator structure 323 includes a plurality of protuberances, such as,but not limited to, bumps, lumps, knobs, humps, juts, projections,prominences, protrusions, bulges, dimples, spikes, or certain desiredsurface area roughness. In certain embodiments, the turbulator structure323 at the inner surface 223 may include at least one thousandprotuberances across the circumference or perimeter of the double wallstructure 122. In some embodiments, the turbulator structure 323 at theinner surface 223 may include at least five thousand protuberancesacross the circumference or perimeter of the double wall structure 122.In still certain embodiments, the turbulator structure 323 may includeat least ten thousand protuberances.

In various embodiments, the turbulator structure including a pluralityof protuberances may improve heat transfer from the flow of fluidthrough the plenum 121 to the outer portion 123 of the inner wall 120.In certain instances, the ranges of quantity of plurality ofprotuberances at the inner surface 223 increase the heat transfercoefficient over known structures. In some embodiments, the outerportion 123 of the inner wall 120, such as depicted at 225, is twice asthick or greater as the inner portion 124 of the inner wall 120, such asdepicted at 227. In other embodiments, the outer portion 123 of theinner wall 120 is between two-times thicker and three-times thicker thanthe inner portion 124 of the inner wall 120. In still other embodiments,the outer portion 123 is greater than twice as thick as the innerportion 124 of the inner wall 120.

Various embodiments of the double wall structure 122 provided hereininclude ranges or quantities that, alone or in combination, may providebenefits not known or previously expected in the art. In one embodiment,a ratio of the quantity of the plurality of protuberances versus thethickness 225 of the outer portion 123 provides particular heat transferbenefits at the frame 100 and the engine 10. In another embodiment, aratio of the thickness 225 of the outer portion 123 versus the thickness227 of the inner portion 124 provides particular heat transfer benefitsat the frame 100 and the engine 10. In still another embodiment, a ratioof the quantity of the plurality of protuberances versus the thickness225 of the outer portion 123 and the thickness 227 of the inner portion124 provides particular heat transfer benefits at the frame 100 and theengine 10. Heat transfer benefits may include desired anti-icing at theinner wall 120, such as receiving and retaining thermal energy at theouter portion 123 and minimizing retained thermal energy at the innerportion 124. Such ratios may desirably improve anti-icing at the innerwall 120 relative to the core flowpath 78. Such ratios may furtherreduce inefficiencies related to heat retention at portions of the frame100 that may not desirably affect icing at the core flowpath 78, such asthe inner portion 124 at the plenum 121. Additionally, or alternatively,heat transfer benefits may include thermal energy retention at the outerportion 123 of the inner wall 120 while reducing or mitigating heat lossor thermal energy transfer to the flow of oxidizer through the coreflowpath 78. As lower oxidizer temperatures upstream of the compressorsection 21 generally provide improved engine performance, the frame 100may provide anti-icing and further reduce efficiency losses at theengine 10 by mitigating increases in inlet air temperature upstream ofthe compressor section 21.

Referring now to FIG. 5, a cutaway perspective view of an exemplaryembodiment of a portion of the frame 100 of the engine 10 is provided.The embodiment depicted in regard to FIG. 5 is configured substantiallysimilarly as shown and described in regard to FIGS. 1-4. Referring alsoto FIG. 6, a cross sectional view of an exemplary embodiment of aportion of the frame 100 of the engine 10 is provided. The embodimentshown and described in regard to FIG. 6 is configured and operablesubstantially similarly as shown and described in regard to FIGS. 1-5.Regarding FIGS. 5-6, the frame 100 further includes one or more plenumwalls 229 extended between the outer portion 123 and the inner portion124 of the double wall structure 122 of the inner wall 120. The plenumwall 229 is extended at least partially along an axial distance of thedouble wall structure 122. The plenum wall 229 sections or divides theplenum 121 into two or more portions divided by the plenum wall 229.

Referring to FIGS. 4-6, the plenum wall 229 may generally include ribsor other features providing structural support at the double wallstructure 122. Structural support provided by the double wall structure122 includes ballistics protection, such as for withstanding foreignobject debris (FOD) ingestion (e.g., bird strikes, ice ingestion, orother non-oxidizer matter that may enter the engine 10). Additionally,or alternatively, the plenum wall 229 may further improve heat transferat the double wall structure 122. In some embodiments, the plenum wall229 provides convective heat transfer from the flow of fluid 92 at thedouble wall structure 122. In still some embodiments, the plenum wall229 additionally or alternatively provides conductive heat transfer fromthe flow of fluid 92 by forming a plurality of flowpaths within theplenum 121, such as further described herein. Additionally, oralternatively, the plenum wall 229 may form high pressure regions of theplenum 121 relative to one or more of the collectors 221, 222 atopposing ends of the plenum 121. In certain embodiments, the plenum 121includes a portion 224 (FIG. 5) positioned forward or upstream of theaft collector 222. In other embodiments, the portion 224 of the plenum121 is positioned aft or downstream of the forward collector 221. Instill various embodiments, the portion 224 of the plenum 121 ispositioned between the forward collector 221 and the aft collector 222.The portion 224 of the plenum 121 includes a cross sectional area 226(FIG. 6) less than a cross sectional area 228 (FIG. 4) one or both ofthe collectors 221, 222. The portion 224 of the plenum 121 may define alow flow region at which the flow of fluid 91 through the plenum 121 isallowed a longer residence time before egressing through the secondplenum opening 128. In various embodiments, the portion 224 of theplenum 121 may generally correspond to the two or more portions dividedby the plenum wall 229.

Referring back to FIGS. 4-6, the forward collector 221, the aftcollector 222, or both may each provide volumes at which pressure and/orflow of fluid in the plenum 121 is normalized or averaged before theflow of fluid 92 egresses into the core flowpath 78. During operation ofan exemplary embodiment of the engine 10, the flow of fluid 91 entersthe plurality of portions 224 of the plenum 121 each divided by theplenum wall 229. Each portion 224 of the plenum 121 may experiencedifferences in pressure, such as due to circumferential or perimetricdifferences in temperature based at least on potential icing conditionsat the inlet end 102. Additionally, or alternatively, each portion 224of the plenum 121 may experience differences in pressure based at leaston obstruction, clogging, or other covering of the first plenum opening126, the second plenum opening 128, or both. As such, the forwardcollector 221 may provide substantially uniform temperature and/orpressure of fluid in the plenum 121. The forward collector 221 mayfurther provide such conditions despite obstruction of a portion of thefirst plenum openings 126 and/or icing conditions from the flow of fluid89 at the inlet end 102 of the frame 100. The substantially uniformtemperature and/or pressure at the forward collector 221 may allow forsubstantially the entire circumference or perimeter of the inner wall120 at the inlet end 102 to receive thermal energy from the flow offluid 91 and transfer thermal energy to the inner wall 120 at least atthe inlet end 102.

Additionally, or alternatively, the aft collector 222 may providesubstantially uniform temperature and/or pressure to the flow of fluid92 egressing the second plenum opening 128. The substantially uniformtemperature and/or pressure of the flow of fluid 92 provided at least bythe aft collector 222 may allow for substantially uniform flowconditions of the flow of oxidizer 89 at the core flowpath 78. Duringoperation of an exemplary embodiment of the engine 10, the aft collector222 may mitigate formation of asymmetric or distorted flow conditions ofthe flow of oxidizer 89 at the core flowpath 78 at or downstream of thesecond plenum openings 128. As such, the flow of oxidizer 89 may receivethe flow of fluid 92 from the second plenum opening 128 withoutproducing undesired turbulence, distortion, wakes, vortices, or otherfluid dynamics at or downstream of the second plenum opening 128.

Furthermore, or alternatively, the compressor section 21 may receive asubstantially uniform flow of oxidizer 89 from the frame 100. It shouldbe appreciated that compressor sections are often challenged to operateunder inlet distortion conditions (e.g., circumferential flowasymmetries due to physical or aerodynamic distortions or variations inflow). As such, the frame 100 may mitigate ice formation at the frame100, and further mitigate other asymmetries or distortions in the flowof oxidizer in the core flowpath 78 that may have an adverse orundesired effect on performance or operability of the compressor section21.

Referring now to FIGS. 7-8, perspective views of embodiments of theframe 100 are provided. Referring further to FIG. 9, a side view ofanother embodiment of the frame 100 is provided. The embodimentsdepicted in regard to FIGS. 7-9 may each be configured substantiallyaccording to one or more embodiments shown and described in regard tothe engine 10 and frame 100 in FIGS. 1-6. Referring more particularly toFIGS. 2-4 and FIGS. 7-9, in various embodiments, the frame 100 includesa passage 230 formed in the outer wall 130. The passage 230 is extendedat least partially circumferentially around the core flowpath 78 throughthe outer wall 130, such as depicted in FIGS. 7-8. In certainembodiments, the passage 230 is extended substantially circumferentiallyaround the core flowpath 78 through the outer wall 130.

Referring to FIGS. 7-8, the passage 230 includes one or more windings231 of the passage 230 extended at least partially circumferentiallythrough the outer wall 130. The passage 230 may further include one ormore turns 233 at which a flow of fluid, depicted via arrows 86, changesfrom a first direction to a second direction. In one embodiment, thewindings 231 are substantially along a circumferential direction Crelative to the axial centerline axis 12. The turn 233 extends at leastpartially along the longitudinal direction L and along thecircumferential direction C to direct the flow of fluid 86 from thefirst direction along the circumferential direction to the seconddirection opposite of the first direction (e.g., from clockwise tocounter-clockwise, or from counter-clockwise to clockwise).

The frame 100 further includes an inlet port 236 and an outlet port 237.The flow of fluid 86(a) is received at the frame 100 to the passage 230at the outer wall 130 through the inlet port 236. The flow of fluid 86generally includes thermal energy that is transferred from the fluid 86in the passage 230 to the outer wall 130 of the frame 100. The passage230 may therefore provide anti-icing at the outer wall 130. The frame100 may further be configured to receive the flow of fluid 86(a) as afirst flow of heated fluid at the outer wall 130 different from the flowof fluid 90, 91, 92 as a second flow of heated fluid at the inner wall120, such as further described herein. As such, the frame 100 may beconfigured to promote anti-icing and/or mitigate distortion at two ormore walls forming the core flowpath 78.

Referring still to FIGS. 7-8, the passage 230 may be configured toreceive the flow of fluid 86(a) through the inlet port 236 andimmediately direct the flow of fluid 86 to the inlet end 102 of theframe 100. The passage 230 may therefore form a first winding 232 at theinlet end 102, such as to provide a greater portion of thermal energy toportions of the frame 100 that may be more prone to icing (e.g., theinlet end 102). The passage 230 may further form a second winding 234distal to the inlet end 102. The passage 230 may still further form oneor more third windings 238 longitudinally between the first winding 232and the second winding 234. As such, it should be appreciated that theframe 100 may form one or more windings 231 of the passage 230 thatprovide for the passage 230 to extend substantially circumferentiallyaround the core flowpath 78 and at least partially along thelongitudinal direction L. It should further be appreciated that thewindings 231 of the passage 230 may generally be configured to positionthe first winding 232 proximal to the inlet end 102 such as to receiveand transfer a greater portion of thermal energy from the flow of fluid86 to the outer wall 130. Furthermore, the windings 231 of the passage230 may generally be configured to position the second winding 234distal to the inlet end 102 (e.g., more proximate to the outlet end 103than the first winding 232) such as to receive and transfer a lesserportion of thermal energy from the flow of fluid 86 to the outer wall130. The winding 231 of the passage 230 may further be configuredgenerally to position the third winding 238 longitudinally between thefirst winding 232 and the second winding 234.

The positioning of the passage 230, such as the first winding 232, thesecond winding 234, the third winding 238, the inlet port 236, and/orthe outlet port 237, may provide certain benefits not previously knownfor inlet ducts. In certain embodiments, the windings 231 of the passage230 are configured to provide a greater desired portion of heat to theouter wall 130 at the inlet end 102 such as to mitigate or eliminateformation of icing at the frame 100. Mitigating or eliminating formationof ice at the frame 100 may mitigate or eliminate risks associated withundesired FOD ingestion into the engine 10. Furthermore, oralternatively, the windings 231 of the passage 230 shown and describedherein may mitigate or eliminate thermal distortion of the frame 100.Embodiments shown and depicted herein may particularly mitigatecircumferential distortions and/or reduce a thermal gradient along thecircumference or perimeter of the outer wall 130. Mitigating oreliminating thermal distortion may improve operability of the engine 10,or mitigate reduction in operability at certain conditions (e.g., aticing conditions, or high thermal gradients generally) by providingsubstantially uniform geometry of the frame 100 for the flow of oxidizer89 therethrough to the core engine 18 (e.g., the compressor section 21).Mitigating or eliminating thermal distortion, or generally reducing thethermal gradient, may further reduce stresses that may be applied to oneor more structure attached directly or indirectly to the frame 100, suchas, but not limited to, the compressor section 21, the bearing assembly150, or one or more rotors or shafts that may extend through the frame100.

Still further, positioning of the passage 230 such as shown anddescribed herein, in addition to embodiments of the double wallstructure 122 at the inner wall 120, may together mitigate or eliminatethermal distortion at the frame 100. In certain embodiments, the passage230 at the outer wall 130 and the double wall structure 122 at the innerwall 120 may together mitigate or eliminate formation of thermaldistortion, icing, or other undesired thermal conditions or distortionsat the frame 100 by reducing geometric changes relative to an innerflowpath or inner annular structure versus an outer flowpath or outerannular structure.

It should be appreciated that in other embodiments (not depicted) thepassage 230 may extend substantially along the longitudinal direction Lsuch that the turns 233 change the flow of fluid 86 within the passage230 from a first direction along the longitudinal direction to a seconddirection opposite of the first direction.

Various embodiments of the frame 100 provided herein may allow for thecore flowpath 78 to extended perimetrically or annularly between theouter wall 130 the inner wall 120. In certain embodiments, the frame 100is allowed to be free of structures, such as vanes, struts, orstructural supports, positioned in the core flowpath 78 between theinner wall 120 and the outer wall 130. In still certain embodiments, theframe 100 is allowed to be free of structures positioned in the coreflowpath 78 between the outer wall 130 and the double wall structure 122of the inner wall 120. In one embodiment, the frame 100 is free ofstructures positioned in the core flowpath 78 between the outer wall 130and the outer portion 123 of the inner wall 120.

Full perimetric or annular extension of the core flowpath 78 between theouter wall 130 and the inner wall 120 may decrease weight, such as byremoving structures unnecessary for flow conditioning for the downstreamstructures (e.g., the compressor section 21, the combustion section 26,or the turbine section 31). Additionally, or alternatively, fullperimetric or annular extension of the core flowpath 78 between theouter wall 130 and the inner wall 120 may mitigate thermal distortion ofthe frame 100 at least at the inlet end 102, such as by de-coupling theouter wall 130 from the inner wall 120 at the inlet end 102, or byde-coupling the outer wall 130 from the inner wall 120 between the inletend 102 and the downstream end of the double wall structure 122 at theinner wall 120 and/or the passage 230 at the outer wall 130.

Referring now to FIGS. 10-11, schematic diagrams are provided of theengine 10 including various embodiments of the frame 100 shown anddescribed in regard to FIGS. 1-9. The engine 10 and frame 100 in FIGS.10-11 are each configured substantially as shown and described in regardto one or more embodiments in regard to FIGS. 1-9. The engine 10 mayfurther include a fluid system 160 configured to provide and receivepressurized flows of fluid, such as, lubrication (e.g., oil or oil-basedfluids), fuel (e.g., liquid and/or gaseous hydrocarbon fuels), orhydraulic fluid. Referring to FIGS. 10-11, in conjunction with FIGS.1-9, the fluid system 160 provides a flow of fluid, such as a firstfluid depicted schematically via arrows 86, to the passage 230 at theframe 100. The flow of fluid 86 defining a first fluid, such as alubricant, a fuel, or a hydraulic fluid, is different from the flow offluid 90, 91, 92 defining a second fluid, such as oxidizer generally, orcompressed air, provided to the outer wall 130. Referring to FIGS.10-11, and in conjunction with embodiments depicted in regard to FIGS.8-9, the flow of fluid 86 enters the passage 230 at the frame 100 via aninlet port 236, such as shown schematically via arrows 86(a). The flowof fluid 86 egresses the passage 230 at the frame 100 via an outlet port237, such as shown schematically via arrows 86(b).

In certain embodiments, such as depicted in regard to FIG. 9, the frame100 further includes a second flow passage 235 at the outer wall 130 inthermal communication with the outer wall 130 before providing the flowof fluid 87 back to the fluid system 160, such as further described anddepicted in regard to FIG. 9. The second flow passage 235 may generallydefine a scavenge conduit through which fluid is egressed from the frame100 and returned to the fluid system 160 (FIGS. 10-11). In certainembodiments, such as depicted in regard to FIGS. 10-11, the second flowpassage 235 is extended in fluid communication from the bearing assembly150 to egress fluid to the fluid system 160. The second flow passage 235is extended at least partially circumferentially at the outer wall 130to provide thermal communication of the flow of fluid 87 within thesecond flow passage 235 with the outer wall 130 and/or the flow ofoxidizer 89 through the core flowpath 78.

Referring back to FIGS. 10-11, certain embodiments of the engine 10include the serial flow of a first fluid 86 from the fluid system 160 tothe frame 100. The first flow of fluid 86, depicted via arrows 86(a), isreceived at the passage 230 via the inlet port 236 (FIGS. 8-9) andegressed through the outlet port 237 (FIGS. 8-9), such as depicted viaarrows 86(b). The egressed flow of fluid 86(b) is provided to thebearing assembly 150, such as through one or more conduits 114 extendedthrough one or more struts 110 (FIG. 3). In various embodiments, theflow of fluid, depicted schematically via arrows 87, is scavenged,removed, or otherwise egresses the bearing assembly 150. In certainembodiments, such as depicted in regard to FIG. 9, the egressed flow offluid 87 will have received thermal energy from the bearing assembly150, such as by acting as a heat sink receiving thermal energy fromrotation of the rotors and bearings. The heated flow of fluid 87 is thenprovided in thermal communication to the outer wall 130 at the secondflow passage 235, such as further described below. The flow of fluid 87may then egress back to the fluid system 160. However, it should beappreciated that in other embodiments in which the second flow passage235 is not provided, the flow of fluid 86 may egress from the bearingassembly 150 back to the fluid system 160 without further thermalcommunication at the outer wall 130 of the frame 100.

Referring back to FIG. 9, in certain embodiments, the second flowpassage 235 is positioned aft or downstream (i.e., downstream relativeto the flow of oxidizer through the core flowpath 78) of the passage230. In such embodiments, the passage 230 positioned at the inlet end102 and extended at least partially circumferentially and wrapped orturned along the longitudinal direction L (e.g., turns 233) provides afirst thermal input from the fluid in the passage 230 in thermalcommunication with the outer wall 130 and/or the flow of oxidizerthrough the core flowpath 78. As thermal energy is transferred from thefluid in the passage 230 to the outer wall 130, the thermal energyoutput decreases from the inlet port 236 to the outlet port 237.Correspondingly, decreasing magnitudes of thermal energy are received atthe outer wall 130 along the longitudinal direction L from the inlet end102 to the outlet end 104. Embodiments of the frame 100 including thesecond flow passage 235 may receive increased magnitudes of thermalenergy extracted from the bearing assembly 150 (FIG. 3) and transfer thethermal energy to portions of the outer wall 130 substantially aft ofthe passage 230 (e.g., aft of the bends, winds, or turns 233 of thepassage 230).

Referring to FIGS. 1-11, during operation of the engine 10, a flow offluid, depicted schematically via arrows 89, is admitted through theinlet end 102 of the frame 100. Generally, as the flow of fluid 89 iscompressed and increases temperature, a portion is utilized as a heatingfluid at the frame 100. A flow of fluid, schematically depicted byarrows 90, is provided to the cavity 125 at the frame 100. In certainembodiments, such as depicted schematically in regard to FIG. 10, theflow of fluid 90 is oxidizer from the compressor section 21. In stillparticular embodiments, the flow of fluid 90 is compressed air routedfrom one or more stages of the compressor section 21, or from downstreamof one or more of a low pressure compressor or a high pressurecompressor. For example, the flow of fluid 90 may be compressed air frombetween a low pressure compressor and a high pressure compressor (i.e.,Station 2.5) of the engine 10. As another example, the flow of fluid 90may be compressed air from or between one or more stages at thecompressor section 21.

In other embodiments, the flow of fluid 90 may be from other pressurizedoxidizer or inert gas sources that may provide thermal energy to theinner wall 120 of the frame 100. In certain embodiments, such asdepicted in regard to FIG. 11, the flow of fluid 90 is provided from thebearing assembly 150 (FIG. 3). In particular embodiments, the flow offluid 90 is provided from a buffer fluid source, damper fluid source, orscavenged therefrom, and routed to the cavity 125.

It should further be appreciated that the flow of fluid 90 is a heatedfluid. In certain embodiments in which the flow of fluid 90 is extractedfrom the compressor section 21, the increased temperature of thepressurized flow of oxidizer provides the thermal energy that isutilized at the inner wall 120. In other embodiments in which the flowof fluid 90 is extracted from the bearing assembly 150, the increasedtemperature from thermal attenuation, cooling, or other thermal controlat the bearing assembly 150, thermal energy is provided to the innerwall 120 from the flow of fluid 90 that was utilized as a thermal sinkat the bearing assembly 150. As provided in regard to FIGS. 1-11,thermal energy from at least a portion of the flow of fluid 90 is thenprovided to the inner wall 120, such as depicted and described in regardto the flow of fluid 91, 92 through the inner wall 120. The fluid 92egresses the inner wall 120 and is mixed with the flow of fluid 89 fromthe inlet end 102 of the core flowpath 78. The flows are mixed, such asdepicted via arrows 93, a portion of which may then be utilized asheating fluid at the frame 100 such as described herein.

As such, the first flow of fluid 86, 87 at the outer wall 130 and thesecond flow of fluid 91, 92 at the inner wall 120 such as in regard toembodiments of the engine 10 and frame 100 shown and described hereinmay provide inlet anti-icing, mitigate structural distortion upstream ofthe compressor section 21 or turbine section 31, improve aerodynamics,compressor performance, and/or compressor operability (e.g., viamitigated structural distortion at the inlet), and improve overallengine efficiency via improved usage of heated fluid at the engine 10.

Referring now to FIG. 12, a perspective view depicting an exemplaryinternal flowpath structure 300 of an embodiment of the frame 100 isgenerally provided. The embodiment depicted in FIG. 12 is viewed fromthe inlet end 102 toward the outlet end 104. Referring also to FIG. 13,a perspective view depicting an exemplary internal flowpath structure300 of another embodiment of the frame 100 is generally provided. Theembodiment depicted in FIG. 13 is viewed from the outlet end 104 towardthe inlet end 102. It should be appreciated that the embodiments of theframe 100 depicted and described in regard to FIGS. 12-13 may beconfigured substantially similarly as one or more embodiments shown anddescribed in regard to FIGS. 1-11. It should further be appreciated thatcertain features or details shown and described in regard to one or moreembodiments of the frame 100 are omitted in FIGS. 12-13 for the sake ofclarity. Furthermore, as further described below, it will be appreciatedthat all or part of the flowpath structure 300 may derive benefits basedat least in part on novel or advantageous positioning of one or more ofthe passages 230, 235 shown and described in regard to FIGS. 1-11.

FIG. 14 provides a detailed view of an embodiment of a nozzle portion303 of the flowpath structure 300. Referring back to FIG. 3, theflowpath structure 300 is positioned at least partially in or throughthe inner wall 120 of the frame 100. As will be further depicted anddescribed in regard to FIGS. 12-14, in still further embodiments, theflowpath structure 300 is defined at least partially through one or morestruts 110. The flowpath structure 300 is configured to provide a flowof fluid to one or more structures aft or downstream (i.e., downstreamrelative to the flow of oxidizer through the core flowpath 78) of theframe 100. In some embodiments, the flow of fluid is provided to theinlet guide vanes 22 and/or the compressor rotor 23 at the compressorsection 21 aft or downstream of the frame 100. In certain embodiments,the flowpath structure 300 is configured to provide a third flow offluid to the aft or downstream structures, in which the third flow offluid is different from the first flow of fluid at the outer wall 130and the second flow of fluid at the inner wall 120. In one embodiment,the third flow of fluid egressed from the flowpath structure 300 is acleaning solution, water or a water-based solution, or other fluid forcleaning one or more structures aft or downstream of the frame 100. Inanother embodiment, the third flow of fluid is a cooling fluid for theflow of fluid 89, 93 at the primary flowpath 77. In such an embodiment,the third flow of fluid egresses into the core flowpath 78 from theflowpath structure 300 via an exit opening 305 such as to cool the flowof oxidizer entering the compressor section 21. The lowered temperatureof oxidizer entering the compressor section 21 may improve compressorperformance or mitigate losses associated with increasing thetemperature of the flow of fluid 89 when mixed with the flow of fluid 92to produce the mixed flow of fluid 93.

Referring still to FIG. 3, and in conjunction with FIGS. 12-14, a curvedor radial portion 320 of the inner wall 120 of the frame 100 defines anexit opening 305 of the flowpath structure 300. The exit opening 305provides fluid communication from the flowpath structure 300 to the coreflowpath 78. The frame 100 defines at the outlet end 104 of the coreflowpath 78 (i.e., at the outlet end 104 of the primary flowpath 77) aradial span 307 (FIG. 3). In various embodiments, the radial span 307defines a dimension extended from the axial centerline axis 12 of theprimary flowpath 77. In certain embodiments, the exit opening 305 of theflowpath structure 300 is positioned within the radial span 307 andforward or upstream of the outlet end 104 of the frame 100. In oneembodiment, the exit opening 305 is positioned at the inner wall 120such that a direct line-of-sight along the longitudinal direction L isprovided relative to one or more structures aft or downstream of theoutlet end 104 of the frame 100.

Referring to FIGS. 1-14, the flowpath structure 300 and the exit opening305 may provide an improved fluid supply system, such as a cleaningsystem, allowed at least in part by positioning the exit opening 305within the radial span 307 between a first wall 131 and the inner wall120, in contrast to known structures that may attempt to provide acleaning fluid from outside of a radial span of a downstream structure.In some embodiments, providing the flowpath structure 300 at the innerwall 120 allows for the outer wall 130 to have space to receive the flowof fluid 86 to provide benefits described in regard to the outer wall130.

Referring briefly to FIG. 14, certain embodiments of the nozzle portion303 of the flowpath structure 300 further include a swirler or vanestructure 304 configured to provide a swirled or solid conical flow offluid toward one or more aft or downstream structures. The flowpathstructure 300 may include a plurality of nozzle portions 303 positionedcircumferentially and symmetrically or asymmetrically around the coreflowpath 78. One or more of the plurality of nozzle portions 303 may beconfigured differently, such as to collectively provide the flow offluid across the circumference of the core flowpath 78.

Referring now to FIG. 15, a cutaway perspective view of a portion of anexemplary embodiment of the frame 100 is provided. The cutawayperspective embodiment is provided viewed from the outlet end 104 towardthe inlet end 102. Referring also to FIG. 16, a cutaway flowpath view ofa portion of the exemplary embodiment of the frame 100 in FIG. 15 isgenerally provided. The embodiments of the frame 100 depicted in regardto FIGS. 15-16 are configured substantially similarly as shown anddescribed in regard to FIGS. 1-14. It should therefore be appreciatedthat certain features or reference numbers may be omitted for the sakeof clarity.

Referring to FIGS. 15-16, and further in conjunction with FIG. 3, theframe 100 further includes a plurality of hollow cores 310. In someembodiments, the core is positioned between walls, such as radiallyextended walls 211, of the second strut 111. In further embodiments, thecore 310 is positioned between a first wall 131 and a second wall 132extended from the splitter 112. In certain embodiments, cores 310 arepositioned radially outward of the outlet end 104. In still certainembodiments, core 310 are positioned axially aft or downstream of thesplitter 112. As such, in various embodiments, the cores 310 are formedbetween walls 211 of the second strut 111, the first wall 131 definingan outer radius 309 of the primary flowpath 77, and the outer wall 130at the second strut 111, such as a portion 213 of the outer wall 130longitudinally at the second strut 111 depicted in FIGS. 3 and 16.

In some embodiments, quantities of the pluralities of the cores 310 arefluidly separated from one another. In certain embodiments, theplurality of cores 310 includes a fluid supply conduit 114 such as toprovide the first flow of fluid 86 (e.g., lubricant) to the bearingassembly 150 (FIG. 3). In another embodiment, the plurality of hollowcores 310 includes a scavenge core 318 through which the first flow offluid 87 (e.g., lubricant) is removed or egressed from the bearingassembly 150. In certain embodiments, the scavenge core 318 is in fluidcommunication with the second flow passage 235 such as to provide theegressed flow of fluid 87 from the bearing assembly 150 to the secondflow passage 235. In still certain embodiments, the plurality of hollowcores 310 includes a thermal management core 314 through which a flow ofcooling fluid, such as a fourth flow of fluid, is provided for thermalmanagement or thermal attenuation of the frame 100. In variousembodiments, the fourth flow of fluid is different or separate from thefirst, second, or third flows of fluid. In still certain embodiments,the plurality of cores 310 includes a services passage 316 through whichelectrical components, cables, connections, manifolds, tubes, wires,sensors, measurement devices, or other electrical or electroniccomponents may be routed through the frame 100, such as to the bearingassembly 150. In still further embodiments, the plurality of cores 310may include at least a portion of the flowpath structure 300, such asshown and described in regard to FIGS. 12-14.

It should be appreciated that the plurality of cores 310, such aspassages 300, 314, 316, 318, are fluidly separated from one another. Assuch, the services passage 316 may define a substantially dry passage.The flowpath structure 300 may define a passage to provide a fluid wash(e.g., water or water-based solution, or other appropriate cleaningsolution) through the exit opening 305 toward the aft or downstreamstructure (e.g., the inlet guide vanes 22, the compressor rotor 23,etc.). The thermal management core 314 may define a passage to provide athermal management fluid at the frame 100 different from the first flowof fluid 86 at the outer wall 130 and/or the second flow of fluid 90,91, 92 at the inner wall 120. The thermal management core 314 may definean air-cooled oil cooler (ACOC), such as cooled by the air through thecore flowpath 78 and/or surrounding the frame 100. The scavenge core 318may define a passage to remove or egress fluid from the bearing assembly150. Still other passages may define dead spaces such as to removeweight from the frame 100.

In certain embodiments, the plurality of cores 310 includes at leastfour fluidly segregated passages, such as described above. In someembodiments, the fluidly segregated passages such as described above mayinclude pluralities of passages, such as two or more scavenge passages,two or more supply passages, two or more services passages, or two ormore thermal management passages. The passages may generally correspondto a bearing assembly, such as a supply or scavenge passage for aforward bearing assembly different from a supply or scavenge passage foran aft bearing assembly. As such, in various embodiments, the pluralityof cores 310 may include at least eleven fluidly segregated passages. Instill another embodiment, the plurality of cores 310 may include sixteenor fewer fluidly separated passages.

Furthermore, the plurality of fluidly segregated cores 310 are definedbetween an outer surface 311 of the outer wall 130 and the outer radius309 of the primary flowpath 77. In certain embodiments, the walls 211 ofthe second strut 111 at least partially defining the cores 310 includesa thickness 209 that provides benefits not previously known or expectedfor frames. Benefits include, but are not limited to, desired heattransfer properties, desired flow rate and pressure loss properties, andsizing relative to a maximum radius at the outer surface 311 of theouter wall 130 and the outer radius 309 of the primary flowpath 77 tothe core engine 18.

Referring back to FIG. 1, embodiments of the engine 10 provided hereinmay include a controller 500 configured to control one or more flows offluid through one or more passages shown and described herein in regardto FIGS. 1-16. The controller 500 included with the engine 10 cancorrespond to any suitable processor-based device, including one or morecomputing devices. The controller 500 can include a processor 512 andassociated memory 514 configured to perform a variety ofcomputer-implemented functions. In various embodiments, the controller500 may be configured to perform steps of a method for anti-icing,thermal management, or distortion mitigation, at an inlet frame at anengine, such as embodiments of the frame 100 provided herein. The stepsmay include flowing a first flow of fluid at an outer wall; flowing asecond flow of fluid at an inner wall, in which the second flow of fluidis different from the first flow of fluid; and adjusting a flow rate ofthe first flow of fluid and/or the second flow of fluid based at leaston a desired temperature at the frame.

As used herein, the term “processor” refers not only to integratedcircuits referred to in the art as being included in a computer, butalso refers to a controller, microcontroller, a microcomputer, aprogrammable logic controller (PLC), an application specific integratedcircuit (ASIC), a Field Programmable Gate Array (FPGA), and otherprogrammable circuits. Additionally, the memory 214 can generallyinclude memory element(s) including, but not limited to, computerreadable medium (e.g., random access memory (RAM)), computer readablenon-volatile medium (e.g., flash memory), a compact disc-read onlymemory (CD-ROM), a magneto-optical disk (MOD), a digital versatile disc(DVD) and/or other suitable memory elements or combinations thereof. Invarious embodiments, the controller 500 may define one or more of a fullauthority digital engine controller (FADEC), a propeller control unit(PCU), an engine control unit (ECU), or an electronic engine control(EEC).

As shown, the controller 500 may include control logic 516 stored inmemory 514. The control logic 516 may include instructions that whenexecuted by the one or more processors 512 cause the one or moreprocessors 512 to perform operations, such as one or more steps orfunctions, flows or flow rates, or desired temperatures describedherein.

Additionally, the controller 500 may also include a communicationsinterface module 510. In various embodiments, the communicationsinterface module 510 can include associated electronic circuitry that isused to send and receive data. As such, the communications interfacemodule 510 of the controller 500 can be used to receive data from theframe 100, the bearing assembly 150, the fluid system 160, a valve 240positioned between the fluid system 160 and the outer wall 130 tocontrol fluid flow or pressure to or from the outer wall 130, or othervalves, sensors, manifolds, or fluid flow, pressure, or temperaturecontrol devices as may be incorporated into the present disclosure. Thecommunications interface module 510 can also be used to communicate withany other suitable components of the engine 10, including any number ofsensors configured to monitor one or more operating parameters of theengine 10. It should be appreciated that the communications interfacemodule 510 can be any combination of suitable wired and/or wirelesscommunications interfaces and, thus, can be communicatively coupled toone or more components of the engine 10 via a wired and/or wirelessconnection.

Various embodiments of the frame 100 shown and described herein may befabricated via one or more manufacturing methods known in the art, suchas, but not limited to, additive manufacturing, binder jetting, or 3Dprinting processes generally, machining processes, material addition orremoval processes, or joining or bonding processes. Manufacturingprocesses may include, but are not limited to, casting, welding,brazing, soldering, or bonding processes. Materials may include thosesuitable for piston assemblies and pressure vessels configured toreceive thermal differentials and operate for desired cycles and poweroutputs, including rigid and flexible wall members, enclosures, andconduits. Although certain exemplary embodiments may preferably beproduced via one or more additive manufacturing processes, it should beappreciated that other manufacturing processes, or combinations thereof,may be utilized. Still further, although certain elements or structuresmay be produced as substantially monolithic structures, certain elementsmay be attached or otherwise coupled via welding, brazing, or mechanicalfasteners, such as, but not limited to, clamps, nuts, bolts, screws, tierods, washers, etc.

As used herein, the terms “additively manufactured” or “additivemanufacturing techniques or processes” refer generally to manufacturingprocesses wherein successive layers of material(s) are provided on eachother to “build-up,” layer-by-layer, a three-dimensional component. Thesuccessive layers generally fuse together to form a monolithic componentwhich may have a variety of integral sub-components.

Although additive manufacturing technology is described herein asproviding fabrication of complex objects by building objectspoint-by-point, layer-by-layer, typically in a vertical direction, othermethods of fabrication are possible and are within the scope of thepresent subject matter. For example, although the discussion hereinrefers to the addition of material to form successive layers, oneskilled in the art will appreciate that the methods and structuresdisclosed herein may be practiced with any additive manufacturingtechnique or manufacturing technology. For example, embodiments of thepresent disclosure may use layer-additive processes, layer-subtractiveprocesses, or hybrid processes. As another example, embodiments of thepresent disclosure may include selectively depositing a binder materialto chemically bind portions of the layers of powder together to form agreen body article. After curing, the green body article may bepre-sintered to form a brown body article having substantially all ofthe binder removed, and fully sintered to form a consolidated article.

Suitable additive manufacturing techniques in accordance with thepresent disclosure include, for example, Fused Deposition Modeling(FDM), Selective Laser Sintering (SLS), 3D printing such as by inkjetsand laserjets, Sterolithography (SLA), Direct Laser Sintering (DLS),Direct Selective Laser Sintering (DSLS), Electron Beam Sintering (EBS),Electron Beam Melting (EBM), Laser Engineered Net Shaping (LENS), LaserNet Shape Manufacturing (LNSM), Direct Metal Deposition (DMD), DigitalLight Processing (DLP), Direct Laser Melting (DLM), Direct SelectiveLaser Melting (DSLM), Selective Laser Melting (SLM), Direct Metal LaserMelting (DMLM), Binder Jetting (BJ), and other known processes.

The additive manufacturing processes described herein may be used forforming components using any suitable material. For example, thematerial may be plastic, metal, concrete, ceramic, polymer, epoxy,photopolymer resin, or any other suitable material that may be in solid,liquid, powder, sheet material, wire, or any other suitable form orcombinations thereof. More specifically, according to exemplaryembodiments of the present subject matter, the additively manufacturedcomponents described herein may be formed in part, in whole, or in somecombination of materials including but not limited to pure metals,nickel alloys, chrome alloys, titanium, titanium alloys, magnesium,magnesium alloys, aluminum, aluminum alloys, and nickel or cobalt basedsuperalloys (e.g., those available under the name Inconel® availablefrom Special Metals Corporation). These materials are examples ofmaterials suitable for use in the additive manufacturing processesdescribed herein, and may be generally referred to as “additivematerials.”

In addition, one skilled in the art will appreciate that a variety ofmaterials and methods for bonding those materials may be used and arecontemplated as within the scope of the present disclosure. As usedherein, references to “fusing” or “binding” may refer to any suitableprocess for creating a bonded layer of any of the above materials. Forexample, if an object is made from polymer, fusing may refer to creatinga thermoset bond between polymer materials. If the object is epoxy, thebond may be formed by a crosslinking process. If the material isceramic, the bond may be formed by a sintering process. If the materialis powdered metal, the bond may be formed by a melting or sinteringprocess, or additionally with a binder process. One skilled in the artwill appreciate that other methods of fusing materials to make acomponent by additive manufacturing are possible, and the presentlydisclosed subject matter may be practiced with those methods.

In addition, the additive manufacturing process disclosed herein allowsa single component (e.g., the frame 100) to be formed from multiplematerials. Thus, the components described herein may be formed from anysuitable mixtures of the above materials. For example, a component mayinclude multiple layers, segments, or parts that are formed usingdifferent materials, processes, and/or on different additivemanufacturing machines. In this manner, components may be constructedwhich have different materials and material properties for meeting thedemands of any particular application. In addition, although thecomponents described herein are constructed entirely by additivemanufacturing processes, it should be appreciated that in alternateembodiments, all or a portion of these components may be formed viacasting, machining, and/or any other suitable manufacturing process.Indeed, any suitable combination of materials and manufacturing methodsmay be used to form these components.

An exemplary additive manufacturing process will now be described.Additive manufacturing processes fabricate components usingthree-dimensional (3D) information, for example a three-dimensionalcomputer model, of the component. Accordingly, a three-dimensionaldesign model of the component may be defined prior to manufacturing. Inthis regard, a model or prototype of the component may be scanned todetermine the three-dimensional information of the component. As anotherexample, a model of the component may be constructed using a suitablecomputer aided design (CAD) program to define the three-dimensionaldesign model of the component.

The design model may include 3D numeric coordinates of the entireconfiguration of the component including both external and internalsurfaces of the component. For example, the design model may define thebody, the surface, and/or internal passageways such as openings, supportstructures, etc. In one exemplary embodiment, the three-dimensionaldesign model is converted into a plurality of slices or segments, e.g.,along a central (e.g., vertical) axis of the component or any othersuitable axis. Each slice may define a thin cross section of thecomponent for a predetermined height of the slice. The plurality ofsuccessive cross-sectional slices together forms the 3D component. Thecomponent is then “built-up” slice-by-slice, or layer-by-layer, untilfinished.

In this manner, the components described herein may be fabricated usingthe additive process, or more specifically each layer is successivelyformed, e.g., by fusing or polymerizing a plastic using laser energy orheat or by sintering or melting metal powder. For example, a particulartype of additive manufacturing process may use an energy beam, forexample, an electron beam or electromagnetic radiation such as a laserbeam, to sinter or melt a powder material. Any suitable laser and laserparameters may be used, including considerations with respect to power,laser beam spot size, and scanning velocity. The build material may beformed by any suitable powder or material selected for enhancedstrength, durability, and useful life, particularly at hightemperatures.

Each successive layer may be, for example, between about 10 μm and 200μm, although the thickness may be selected based on any number ofparameters and may be any suitable size according to alternativeembodiments. Therefore, utilizing the additive formation methodsdescribed above, the components described herein may have cross sectionsas thin as one thickness of an associated powder layer, e.g., 10 μm,utilized during the additive formation process. In certain embodiments,the walls 211 at the cores 310 are at least 1000 μm, or betweenapproximately 1000 μm and approximately 2000 μm, or betweenapproximately 1200 μm and approximately 1900 μm. It should beappreciated that particular ranges of thickness 209 (FIG. 16) at thewalls 211 such as provided herein may provide particular benefits to theframe 100, such as desired heat transfer to one or more fluids throughthe cores 310 and desired or mitigated pressure loss through the cores310, such as to provide desired fluid flowrate and pressure through thecores 310 and desired heat transfer to and from the fluids within theframe 100. Still further, it should be appreciated that variousparticular ranges of thickness 209 of the walls 211 provide particularbenefits for allowing desired heat transfer and flow through the cores310 while constrained between the outer radius 309 of the primaryflowpath 77 and the radius of the outer surface 311 of the outer wall130. As such, embodiments of the frame 100 including ranges of wallthickness provided herein may particularly provide desired heat transferand flow characteristics for turboshaft or turboprop engines sized toproduce up to approximately 4500 horsepower. Such engine sizing mayparticularly be in regard to the outer radius 309 of the primaryflowpath 77 at the frame 100 aft of the splitter 112, and further inregard to a maximum radius of the outer surface 311 of the outer wall130 of the frame 100. The ranges provided herein may further provideimproved heat transfer, fluid flow characteristics, and decreased engineweight, together improving efficiency and performance of the engine 10including the frame 100.

In addition, utilizing an additive process, the surface finish andfeatures of the components may vary as need depending on theapplication. For example, the surface finish may be adjusted (e.g., madesmoother or rougher) by selecting appropriate laser scan parameters(e.g., laser power, scan speed, laser focal spot size, etc.) during theadditive process, especially in the periphery of a cross-sectional layerwhich corresponds to the part surface. For example, a rougher finish maybe achieved by increasing laser scan speed or decreasing the size of themelt pool formed, and a smoother finish may be achieved by decreasinglaser scan speed or increasing the size of the melt pool formed. Thescanning pattern and/or laser power can also be changed to change thesurface finish in a selected area.

After fabrication of the component is complete, various post-processingprocedures may be applied to the component. For example, post processingprocedures may include removal of excess powder by, for example, blowingor vacuuming. Other post processing procedures may include a stressrelief process. Additionally, thermal, mechanical, and/or chemical postprocessing procedures can be used to finish the part to achieve adesired strength, surface finish, a decreased porosity decreasing and/oran increased density (e.g., via hot isostatic pressing), and othercomponent properties or features.

It should be appreciated that one skilled in the art may add or modifyfeatures shown and described herein to facilitate manufacture of theframe 100 provided herein without undue experimentation. For example,build features, such as trusses, grids, build surfaces, or othersupporting features, or material or fluid ingress or egress ports, maybe added or modified from the present geometries to facilitatemanufacture of embodiments of the frame 100 based at least on a desiredmanufacturing process or a desired particular additive manufacturingprocess.

Notably, in exemplary embodiments, several features of the componentsdescribed herein were previously not possible due to manufacturingrestraints. However, the present inventors have advantageously utilizedcurrent advances in additive manufacturing techniques to developexemplary embodiments of such components generally in accordance withthe present disclosure. While certain embodiments of the presentdisclosure may not be limited to the use of additive manufacturing toform these components generally, additive manufacturing does provide avariety of manufacturing advantages, including ease of manufacturing,reduced cost, greater accuracy, etc.

In this regard, utilizing additive manufacturing methods, evenmulti-part components may be formed as a single piece of continuousmetal, and may thus include fewer sub-components and/or joints comparedto prior designs. The integral formation of these multi-part componentsthrough additive manufacturing may advantageously improve the overallassembly process, reduce potential leakage, reduce thermodynamic losses,improve thermal energy transfer, or provide higher power densities. Forexample, the integral formation reduces the number of separate partsthat must be assembled, thus reducing associated time, overall assemblycosts, reduces potential leakage pathways, or reduces potentialthermodynamic losses. Additionally, existing issues with, for example,leakage, may advantageously be reduced. Still further, joint qualitybetween separate parts may be addressed or obviated by the processesdescribed herein, such as to desirably reduce leakage, assembly, andimprove overall performance.

Also, the additive manufacturing methods described above provide muchmore complex and intricate shapes and contours of the componentsdescribed herein to be formed with a very high level of precision. Forexample, such components may include thin additively manufacturedlayers, cross sectional features, and component contours. As anotherexample, additive manufacturing may provide heat exchanger surfaceareas, volumes, passages, conduits, or other features that may desirablyimprove heat exchanger efficiency or performance, or overall engine orsystem performance. In addition, the additive manufacturing processprovides the manufacture of a single component having differentmaterials such that different portions of the component may exhibitdifferent performance characteristics. The successive, additive steps ofthe manufacturing process provide the construction of these novelfeatures. As a result, the components described herein may exhibitimproved functionality and reliability.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to practice the invention, including making and using any devices orsystems and performing any incorporated methods. The patentable scope ofthe invention is defined by the claims, and may include other examplesthat occur to those skilled in the art. Such other examples are intendedto be within the scope of the claims if they include structural elementsthat do not differ from the literal language of the claims, or if theyinclude equivalent structural elements with insubstantial differencesfrom the literal languages of the claims.

Further aspects of the invention are provided by the subject matter ofthe following clauses:

1. A thermal management system for a heat engine, the system includingan inner wall extended from an inlet end to an outlet end. The innerwall forms at least in part a core flowpath and a cavity. The coreflowpath and the cavity are separated by a double wall structure at theinner wall. The double wall structure forms a plenum, a first openingproviding fluid communication between the cavity and the plenum, and asecond opening providing fluid communication between the plenum and thecore flowpath. The inner wall is configured to receive a first flow offluid. An outer wall is extended from the inlet end toward the outletend. The outer wall forms a passage extended at least partially aroundthe core flowpath. The outer wall at least partially forms the coreflowpath. The outer wall is configured to receive a second flow of fluidfluidly separated from the core flowpath.

2. The system of any clause herein, the system including a fluid systemconfigured to provide the second flow of fluid to the passage at theouter wall.

3. The system of any clause herein, wherein the second flow of fluid isa lubricant, a fuel, a hydraulic fluid, or combinations thereof.

4. The system of any clause herein, wherein the first flow of fluid isan oxidizer.

5. The system of any clause herein, wherein the passage includes one ormore windings of the passage extended at least partiallycircumferentially through the outer wall.

6. The system of any clause herein, wherein the passage includes one ormore turns at which the first flow of fluid changes from a firstdirection to a second direction opposite of the first direction.

7. The system of any clause herein, wherein the passage includes a firstwinding positioned at the inlet end.

8. The system of any clause herein, wherein the passage includes asecond winding positioned longitudinally aft of the first winding,wherein the first winding is configured to provide a greater portion ofthermal energy from the first flow of fluid at the inlet end than thesecond winding aft of the first winding.

9. The system of any clause herein, wherein the passage includes a thirdwinding positioned longitudinally between the first winding and thesecond winding, wherein the second winding is positioned distal to theinlet end.

10. The system of any clause herein, wherein the passage is in fluidcommunication with a bearing assembly, the passage configured to providethe second flow of fluid to the bearing assembly.

11. The system of any clause herein, wherein the outer wall defines asecond flow passage extended at least partially around the coreflowpath.

12. The system of any clause herein, wherein the second flow passage isin fluid communication with the bearing assembly, and wherein the secondflow passage is configured to receive the second flow of fluid from thebearing assembly.

13. The system of any clause herein, wherein the second flow passage ispositioned aft of the passage along the longitudinal direction.

14. The system of any clause herein, the outer wall forming an inletport and an outlet port each in fluid communication with the passage,wherein the inlet port is configured to receive the second flow of fluidinto the passage, and wherein the outlet port is configured to egressthe second flow of fluid to the bearing assembly.

15. The system of any clause herein, wherein the outer wall is radiallyspaced apart from the inner wall, and wherein the plenum at the innerwall extends from the inlet end toward the outlet end, and wherein thepassage at the outer wall extends from the inlet end toward the outletend.

16. The system of any clause herein, wherein the core flowpath isextended annularly or perimetrically between the outer wall and theinner wall.

17. A turbo machine, the turbo machine defining an inlet end and anoutlet end and a core flowpath. The turbo machine including a compressorsection configured to generate a first flow of fluid, a fluid systemconfigured to generate a second flow of fluid to the passage, and aninlet frame wherein the compressor section is positioned at the outletend of inlet frame. The inlet frame includes an inner wall extended fromthe inlet end to the outlet end, the inner wall forming at least in partthe core flowpath and a cavity. The cavity is positioned inward of theinner wall, and the core flowpath and the cavity are separated by adouble wall structure at the inner wall. The double wall structureincludes a plenum extended from the inlet end toward the outlet end ofthe inlet frame. A first opening provides fluid communication betweenthe cavity and the plenum, and a second opening provides fluidcommunication between the plenum and the core flowpath. The inner wallis configured to receive the first flow of fluid from the compressorsection. An outer wall is extended from the inlet end toward the outletend of the frame. The outer wall forms a passage extended at leastpartially around the core flowpath, and the outer wall at leastpartially forms the core flowpath. The outer wall is configured toreceive the second flow of fluid from the fluid system, the second flowfluidly separated from the first flow of fluid.

18. The turbo machine of any clause herein, wherein the first flow offluid is an oxidizer from the compressor section, and wherein the secondflow of fluid is a lubricant from the fluid system.

19. The turbo machine of any clause herein, wherein the passage includesone or more windings of the passage extended at least partiallycircumferentially through the outer wall, wherein the one or morewindings includes a first winding positioned at the inlet end of theinlet frame and a second winding positioned distal to the first winding,the first winding configured to receive the second flow of fluid beforethe second winding.

20. The turbo machine of any clause herein, the inlet frame forming aninlet port and an outlet port at the outer wall each in fluidcommunication with the passage. The inlet port is configured to receivethe second flow of fluid into the passage from the fluid system, and theoutlet port is configured to egress the second flow of fluid from theouter wall.

21. A turbo machine including the frame of any preceding clause.

22. A frame for a heat engine, the frame including an inner wallextended from an inlet end to an outlet end. The inner wall forms atleast in part a core flowpath, the inner wall including a plenum definedbetween an outer portion of the inner wall and an inner portion of theinner wall. A cavity is defined inward of the inner portion of the innerwall, and the inner wall forms a first plenum opening providing fluidcommunication between the cavity and the plenum, and wherein the innerwall forms a second plenum opening providing fluid communication betweenthe plenum and the core flowpath.

23. The frame of any clause herein, the frame including a plenum wallextended within the plenum between the outer portion and the innerportion of the inner wall.

24. The frame of any clause herein, wherein the plenum wall is extendedco-directional to the inner wall.

25. The frame of any clause herein, wherein the inner wall forms acollector cavity within the plenum positioned upstream or downstream ofthe plenum wall.

26. The frame of any clause herein, wherein the inner wall forms a highpressure region between the plenum wall, the outer portion, and theinner portion, the high pressure region positioned upstream ordownstream of the collector cavity.

27. The frame of any clause herein, wherein the high pressure regionincludes a cross sectional area less than the collector cavity.

28. The frame of any clause herein, wherein the first plenum opening isformed through the inner portion in direct fluid communication with thehigh pressure region.

29. The frame of any clause herein, wherein the first plenum opening isformed through the inner portion in direct fluid communication with thecollector cavity.

30. The frame of any clause herein, wherein the second plenum opening isformed through the outer portion in direct fluid communication with thecollector cavity.

31. The frame of any clause herein, wherein the collector cavityincludes an aft collector positioned aft of a plenum wall, wherein thesecond plenum opening is formed through the outer portion at the aftcollector.

32. The frame of any clause herein, wherein the collector cavityincludes a forward collector positioned forward of a plenum wall,wherein the first plenum opening is formed through the inner portion atthe forward collector.

33. The frame of any clause herein, wherein the forward collector ispositioned at the inlet end of the frame.

34. The frame of any clause herein, the frame including an outer wallextended from the inlet end toward the outlet end of the frame, whereinthe outer wall and the inner wall together form the core flowpath, theouter wall forming a passage extended at least partially around the coreflowpath, the outer wall at least partially defining the core flowpath.

35. The frame of any clause herein, wherein the inner wall is configuredto receive a first flow of fluid and the outer wall is configured toreceive a second flow of fluid different from the first flow of fluid.

36. The frame of any clause herein, wherein the second flow of fluid isa lubricant, a fuel, a hydraulic fluid, or combinations thereof, andwherein the first flow of fluid is an oxidizer.

37. The frame of any clause herein, the outer portion including an innersurface, wherein the inner surface includes a turbulator structure.

38. The frame of any clause herein, wherein the outer portion of theinner wall is twice as thick or greater as the inner portion of theinner wall.

39. A heat engine, the heat engine including the frame of any precedingclause.

40. A heat engine, the heat engine including a frame, the frameincluding an inner wall extended from an inlet end to an outlet end. Theinner wall forms at least in part a primary flowpath and a plenum isformed between an outer portion of the inner wall and an inner portionof the inner wall. A cavity is formed inward of the inner portion of theinner wall. The inner wall forms a first plenum opening providing fluidcommunication between the cavity and the plenum. The inner wall forms asecond plenum opening providing fluid communication between the plenumand the primary flowpath.

41. The heat engine of any clause herein, wherein the inner wall forms acollector cavity within the plenum positioned forward or aft of a plenumwall, and wherein the second plenum opening is formed through the outerportion of the inner wall in direct fluid communication with thecollector cavity aft of the plenum wall.

42. The heat engine of any clause herein, the frame including an outerwall extended from the inlet end toward the outlet end of the frame. Theouter wall and the inner wall together form the core flowpath. The outerwall forms a passage extended at least partially around the coreflowpath and at least partially forms the core flowpath.

43. A turbo machine, the turbo machine comprising an inner wall extendedfrom an inlet end to an outlet end, the inner wall comprising a doublewall structure, wherein a plenum is formed within the double wallstructure, and wherein the double wall structure comprises an openingconfigured to provide fluid communication of a first flow of fluidbetween the plenum through the double wall structure. An outer wall isextended from the inlet end toward the outlet end, the outer wallforming a passage within the outer wall. The outer wall is configured toreceive a second flow of fluid, the second flow fluidly separated fromthe first flow of fluid. The inner wall and the outer wall together forma flowpath between the inner wall and the outer wall. A flowpathstructure is formed at least in part within the inner wall. The flowpathstructure is configured to receive a third flow of fluid therethrough.The third flow of fluid is separate from the first flow of fluid. Theflowpath structure includes an exit opening configured to provide fluidcommunication from the flowpath structure to the flowpath.

44. The turbo machine of any clause herein, wherein the flowpathcomprises a radial span, and wherein the exit opening of the flowpathstructure is positioned within the radial span.

45. The turbo machine of any clause herein, the turbo machine includinga downstream structure positioned downstream of the exit opening. Theexit opening is positioned upstream in line-of-sight relative to thedownstream structure.

46. The turbo machine of any clause herein, wherein the downstreamstructure is a compressor section.

47. The turbo machine of any clause herein, wherein the downstreamstructure is a compressor vane of the compressor section.

48. The turbo machine of any clause herein, wherein the inner wallcomprises a radial portion, and wherein the exit opening is positionedat the radial portion of the inner wall.

49. The turbo machine of any clause herein, wherein the flowpathstructure comprises a nozzle portion positioned at the exit opening.

50. The turbo machine of any clause herein, wherein the nozzle portioncomprises a vane structure configured to provide a swirled flow of thethird flow of fluid.

51. The turbo machine of any clause herein, wherein the first flow offluid is an oxidizer, the second flow of fluid is one or more of alubricant, a fuel, or a hydraulic fluid, and wherein the third flow offluid within the flowpath structure is a fluidly separate from the firstflow of fluid and the second flow of fluid.

52. The turbo machine of any clause herein, wherein the third flow offluid is a cleaning solution.

53. The turbo machine of any preceding clause, the turbo machinecomprising the frame of any preceding clause.

54. A frame for a heat engine, the frame including an inner wall atleast partially forming a primary flowpath, the inner wall at leastpartially forming a flowpath structure within the inner wall, theflowpath structure configured to receive a flow of fluid therethrough.The flow of fluid in the flowpath structure is separate from a flow offluid through the primary flowpath. The flowpath structure includes anexit opening configured to provide fluid communication from the flowpathstructure to the primary flowpath.

55. The frame of any clause herein, wherein the primary flowpathcomprises a radial span, and wherein the exit opening of the flowpathstructure is positioned radially within the radial span of the primaryflowpath.

56. The frame of any clause herein, wherein the inner wall comprises aradial portion, and wherein the exit opening is positioned at the radialportion of the inner wall.

57. The frame of any clause herein, wherein the flowpath structurecomprises a nozzle portion positioned at the exit opening.

58. The frame of any clause herein, wherein the nozzle portion comprisesa vane structure configured to provide a swirled flow of the flow offluid through the exit opening into the primary flowpath.

59. A turbo machine including the frame of any preceding clause.

60. A turbo machine, the turbo machine forming a flowpath extendedtherethrough, the turbo machine including a compressor sectioncomprising a compressor vane and a compressor rotor, and a framepositioned upstream of the compressor section. The flowpath is extendedthrough the frame and the compressor section. The frame includes aninternal flowpath structure configured to receive a flow of fluidtherethrough. The flowpath structure forms an exit opening positionedwithin a radial span of the flowpath. The exit opening is configured toprovide the flow of fluid from the flowpath structure to the compressorsection downstream of the exit opening at the frame.

61. The turbo machine of any clause herein, the frame including aplurality of hollow cores positioned between a strut at the frame,wherein the plurality of hollow cores is fluidly separated from oneanother.

62. The turbo machine of any clause herein, wherein the flowpathstructure is formed at least in part at one of the cores.

63. The turbo machine of any clause herein, wherein the exit opening ispositioned upstream in line-of-sight relative to the compressor section.

64. The turbo machine of any clause herein, wherein the flowpathstructure includes a nozzle portion positioned at the exit opening,wherein the nozzle portion is configured to provide a swirled flow offluid to the compressor section.

65. The frame of any preceding clause, wherein one or more of theplurality of hollow cores is defined between walls of the strut.

66. The frame of any preceding clause, wherein the wall at the hollowcore is at least 1000 μm thick.

67. The frame of any preceding clause, wherein the wall is between 1000μm and 2000 μm thick.

68. The frame of any preceding clause, wherein the wall is between 1200μm and 1900 μm thick.

69. The frame of any preceding clause, wherein the plurality of hollowcores is fluidly segregated from one another.

70. The frame of any preceding clause, wherein the plurality of hollowcores is defined between an outer surface of the outer wall and an outerradius of the primary flowpath.

71. The frame of any preceding clause, comprising at least four fluidlysegregated passages.

72. The frame of any preceding clause, comprising sixteen or fewerfluidly segregated passages.

73. The frame of any preceding clause, comprising at least elevenfluidly segregated passages.

74. The frame of any preceding clause, wherein the plurality of hollowcores forms a plurality of fluidly segregated passages.

75. The frame of any preceding clause, wherein the plurality of hollowcores comprises two or more scavenges passages, two or more supplypassages, two or more services passages, and two or more thermalmanagement passages.

76. The frame of any preceding clause, wherein the plurality of hollowcores is positioned axially aft of a splitter, the splitter separatingthe core flowpath into a primary flowpath and a secondary flowpath.

77. The frame of any preceding clause, wherein the plurality of hollowcores is formed between a wall of a strut, a first wall defining anouter radius of the primary flowpath, and an outer wall of the frame atthe strut.

What is claimed is:
 1. A thermal management system for a heat engine,the system comprising: an inner wall extended from an inlet end to anoutlet end, the inner wall forming at least in part a core flowpath anda cavity, wherein the core flowpath and the cavity are separated by adouble wall structure formed by at least a portion of the inner wall,and wherein the double wall structure comprises a plenum, a firstopening providing fluid communication between the cavity and the plenum,the plenum extending from a first end near the inlet end to a second endtoward the outlet end, a second opening providing fluid communicationbetween the plenum and the core flowpath, the second opening locatedcloser to the second end than the first end, the inner wall configuredto receive a first flow of fluid; and an outer wall extended from theinlet end toward the outlet end, the outer wall forming a passageextended at least partially around the core flowpath, the outer wall atleast partially forming the core flowpath, wherein the outer wall isconfigured to receive a second flow of fluid fluidly separated from thecore flowpath.
 2. The system of claim 1, comprising: a fluid systemconfigured to provide the second flow of fluid to the passage at theouter wall.
 3. The system of claim 2, wherein the second flow of fluidis a lubricant, a fuel, a hydraulic fluid, or combinations thereof. 4.The system of claim 3, wherein the first flow of fluid is an oxidizer.5. The system of claim 1, wherein the passage comprises one or morewindings of the passage extended at least partially circumferentiallythrough the outer wall.
 6. The system of claim 5, wherein the passagecomprises one or more turns at which the first flow of fluid changesfrom a first direction to a second direction opposite of the firstdirection.
 7. The system of claim 5, wherein the passage comprises afirst winding positioned at the inlet end.
 8. The system of claim 7,wherein the passage comprises a second winding positioned longitudinallyaft of the first winding, wherein the first winding is configured toprovide a greater portion of thermal energy from the first flow of fluidat the inlet end than the second winding aft of the first winding. 9.The system of claim 8, wherein the passage comprises a third windingpositioned longitudinally between the first winding and the secondwinding, wherein the second winding is positioned distal to the inletend.
 10. The system of claim 1, wherein the passage is in fluidcommunication with a bearing assembly, the passage configured to providethe second flow of fluid to the bearing assembly.
 11. The system ofclaim 10, wherein the outer wall defines a second flow passage extendedat least partially around the core flowpath.
 12. The system of claim 11,wherein the second flow passage is in fluid communication with thebearing assembly, and wherein the second flow passage is configured toreceive the second flow of fluid from the bearing assembly.
 13. Thesystem of claim 11, wherein the second flow passage is positioned aft ofthe passage along the longitudinal direction.
 14. The system of claim10, the outer wall forming an inlet port and an outlet port each influid communication with the passage, wherein the inlet port isconfigured to receive the second flow of fluid into the passage, andwherein the outlet port is configured to egress the second flow of fluidto the bearing assembly.
 15. The system of claim 1, wherein the outerwall is radially spaced apart from the inner wall, and wherein theplenum at the inner wall extends from the inlet end toward the outletend, and wherein the passage at the outer wall extends from the inletend toward the outlet end.
 16. The system of claim 1, wherein the coreflowpath is extended annularly or perimetrically between the outer walland the inner wall.
 17. A turbo machine, the turbo machine defining acore flowpath, the turbo machine comprising: a compressor sectionconfigured to generate a first flow of fluid; a fluid system configuredto generate a second flow of fluid to a passage; and an inlet framewherein the compressor section is positioned at an outlet end of theinlet frame, the inlet frame comprising: an inner wall extended from aninlet end to the outlet end, the inner wall forming at least in part thecore flowpath and a cavity, the cavity positioned inward of the innerwall, wherein the core flowpath and the cavity are separated by a doublewall structure formed by at least a portion of the inner wall, andwherein the double wall structure comprises a plenum extended from theinlet end toward the outlet end of the inlet frame, the plenum extendingfrom a first end near the inlet end to a second end toward the outletend, wherein a first opening provides fluid communication between thecavity and the plenum, and wherein a second opening provides fluidcommunication between the plenum and the core flowpath, the secondopening located closer to the second end than the first end, the innerwall configured to receive the first flow of fluid from the compressorsection; and an outer wall extended from the inlet end toward the outletend of the inlet frame, the outer wall forming the passage extended atleast partially around the core flowpath, the outer wall at leastpartially forming the core flowpath, wherein the outer wall isconfigured to receive the second flow of fluid from the fluid system,the second flow of fluid fluidly separated from the first flow of fluid.18. The turbo machine of claim 17, wherein the first flow of fluid is anoxidizer from the compressor section, and wherein the second flow offluid is a lubricant from the fluid system.
 19. The turbo machine ofclaim 17, wherein the passage comprises one or more windings of thepassage extended at least partially circumferentially through the outerwall, wherein the one or more windings comprises a first windingpositioned at the inlet end of the inlet frame and a second windingpositioned distal to the first winding, the first winding configured toreceive the second flow of fluid before the second winding.
 20. Theturbo machine of claim 17, the inlet frame comprising an inlet port andan outlet port at the outer wall each in fluid communication with thepassage, wherein the inlet port is configured to receive the second flowof fluid into the passage from the fluid system, and wherein the outletport is configured to egress the second flow of fluid from the outerwall.